arkoma
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Fritted Glass
OK, just received my first piece of glass with a fritted disk, a little 60ml 24/40 Buchner funnel. How do ya clean the frit?
"We believe the knowledge and cultural heritage of mankind should be accessible to all people around the world, regardless of their wealth, social
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BromicAcid
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Depends on what is on the frit but usually it involves soaking since you can't really carry out too much mechanical manipulation without compromising
the integrity and performance of the frit. Usually though the frit is soaked in something that will prove to be volatile so it can be cleaned by
being blown or baked dry and not have residue. For example in my quant class we did a quantitative analysis of silver by forming silver chloride.
This was collected on a sintered glass frit. For cleaning all of our frits were soaked in concentrated ammonium hydroxide solution before having
ammonium hydroxide run through them and oven dried. I have seen nitric used a bit. Piranha even though it doesn't fit the above criteria also gets
some use for hard to clean bits. Of course if standard solvents work go for those instead.
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Texium
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One time I had to clean mine with chromic acid when I got a bunch of carbon gunk stuck in it. It worked, but since then, I've tried to avoid using it
for anything that nasty. Most of the time soaking it in a suitable solvent for whatever it is and then pulling some fresh solvent through it a few
times will be sufficient. Strong bases should be avoided though since it can make your frit more porous than it's supposed to be.
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macckone
Dispenser of practical lab wisdom
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If there are metal compounds then use nitric acid. It will dissolve everything but sulfates.
For carbon gunk piranha solution is best but never use it if there are metals present that might
form insoluble sulfates. Hydrochloric acid will work on most metal carbonates and hydroxides
but forms insoluble salts with things like silver and lead. Otherwise use a suitable solvent.
Acetone, toluene, hexane, ethanol and water are good examples.
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Texium
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Yeah, I would have used piranha rather than chromic acid if I had more concentrated peroxide at the time. The chromic acid worked wonders, though it
does make a toxic mess that's a pain to clean up which can be avoided with piranha.
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HeYBrO
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You can use fenton's reagent for organic gunk aswell, it is conc. H2O2 and iron sulphate if i remember correctly.
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ave369
Eastern European Lady of Mad Science
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If there are metals with insoluble sulfates, use chromonitric acid. It is made the same way as chromic acid,but with fuming nitric instead of
sulfuric.
Smells like ammonia....
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